* config/tc-mips.c (dummy_opcode): Delete.

	(nop_insn, mips16_nop_insn): New variables.
	(NOP_INSN): New macro.
	(insn_length, create_insn, install_insn, move_insn, add_fixed_insn)
	(add_relaxed_insn, insert_into_history, emit_nop): New functions.
	(md_begin): Initialize nop_insn and mips16_nop_insn.
	(append_insn): Use the new emit_nop function to add nops, recording
	them in the history buffer.  Use add_fixed_insn or add_relaxed_insn
	to reserve room for the instruction and install_insn to install the
	final form.  Use insert_into_history to record the instruction in
	the history buffer.  Use move_insn to do delay slot filling.
	(mips_emit_delays): Use add_fixed_insn instead of the emit_nop macro.
	(macro_build, mips16_macro_build, macro_build_lui, mips_ip)
	(mips16_ip): Use create_insn to initialize mips_cl_insns.